The invention concerns a device for testing motor vehicle wheels, tires, wheel hubs, wheel bearings, and wheel bolts under loading conditions similar to operating conditions, including
(a) a mounting device for pivoting attachment of a vehicle wheel and for swiveling the same in different camber angles;
(b) a drum located around the vehicle wheel in such a way that the vehicle wheel can be brought into rolling contact with the inner circumferential surface of the drum via a tire located on the wheel;
(c) a vertical or radial loading device which, in order to apply a vertical or radial force acting in the vertical or radial direction of the vehicle wheel onto the mounting device, is connected with the latter;
(d) a lateral or axial loading device for applying a lateral or axial force acting in the lateral or axial direction of the vehicle wheel, in order to apply the lateral or axial force onto the mounting device, the lateral or axial loading device being connected with the mounting device;
(e) at least one ring located on the inner circumferential surface of the drum, which ring is arranged as a thrust ring adjacent to the tire and the side of the vehicle wheel and is beveled on the side tuned toward the tire; and
(f) a device for turning the drum;
(g) the vertical or radial loading device and the lateral or axial loading device each being connectively hinged with the mounting device;
The former fatigue strength investigation methods for motorcycle wheels are, above all, the following:
(1) roll testing under pure vertical force;
(2) torsion testing with clamping of the rim; and
(3) driving test with motorcycles;
The disadvantages of these above-mentioned testing methods are, both with respect to conducting them as well as the application thereof, in particular the following:
(i) In the case of rolling testing under pure vertical force, and in the case of torsion testing with clamping of the rim, none of the deformation corresponding to actual driving practice is created, so that these testing methods provide only partial results, the evaluation of which is complicated and problematical for practical application.
(ii) In the case of the driving tests with motorcycles there is no sufficient reproducibility of the stress, so that the driving tests are only conditionally usable for the construction of motorcycles, in addition the test driver, in particular in the case of extreme loads in the driving tests, is exposed to significant dangers.
(iii) Finally, in the case of application of the above-mentioned testing methods, tedious, time- and cost-consuming tests of the motorcycle wheels are required which, on the one hand, lead to a corresponding increase in the final sales costs of the motorcycles and, on the other hand, to a relatively long development time for new motorcycle models.
The object of the invention is, in particular, to make available a device for testing motorcycle wheels, which makes it possible to test under loading conditions close to operating conditions with reproducibility of the stress and with reduced expenditure of time and costs, so that the results of the tests conducted with this device can be transferred to the practice of motorcycle production relatively reliably and without complications, without the tests being relatively tedious as well as time- and cost-consuming.
This object is solved with a device of the type mentioned initially, from the applicant""s European patent 63 245 and U.S. Pat. No. 4,475,383 and, in a modified form which does not possess the last feature of the features (a) to (g) of the features mentioned initially, from DE 33 41 7212 C2, in that
(1) the mounting device is mounted capable of moving in such a way that the vehicle wheel can be pivoted around the wheel contact point for automatic camber adjustment; and
(2) the mounting device includes a mount for at least one motorcycle wheel as a vehicle wheel with one-sided attachment of the mount on the remaining part of the mounting device.
In a preferred embodiment of the device in accordance with the invention, the mount for the motorcycle wheel is attached via a flexible bearing to the remaining part of the mounting device, therefore the loading structure.
An attachment arrangement for a brake, in particular a disk brake, designed for the motorcycle wheel, in or on the mount, so that braking forces and acceleration forces can be applied via the brake, in particular the disk brake, with corresponding direction of rotation of the drum simultaneously with the vertical forces and lateral forces acting via the mounting device, therefore force combinations, as they appear in the actual driving operation of a motorcycle.
As compared with vehicle wheels for automobiles and utility vehicles, the diameter of the drum is chosen so that it is significantly larger than that of the motorcycle wheel, preferably 1.2 to 2.5 times as large as the diameter of the motorcycle wheel, so that a loading of the motorcycle wheel similar to operating conditions is provided at the wheel contact point.
The form of the thrust ring or of the two thrust rings, which in accordance with the invention preferably is designed so that it is adapted in a particular and optimal way to the conditions of motor vehicle wheel tires for serviceability tests with the least possible wear, by the thrust ring having:
(a) an early, relatively steep leading edge,
(b) a flat middle edge opposite this,
(c) a relatively steep end edge, and
(d) a rounding on the inner projection.
Finally, the device is designed according to the invention so that an inner drum is provided for strength testing of an original brake by simulation of braking forces with relatively large angle of grip.
The preceding, as well as further advantages and features of the invention are described and explained below by means of a particularly preferred embodiment of the device in accordance with the invention presented in the figures.